Lots of guys over on the SASS wire got recall notices, and a few experienced the malfunction. In the first 500 or so new Vaqueros, there is a potential problem with the firing pin sticking in the forward position. At least, that's what I've been told. I stuck with the original frame Vaqueros.
The smaller framed Vaqueros aren't weaker than Colts, they are in between the Colt and the large original Vaquero in strength. Brian Pearce wrote an article giving loads for the new Ruger frame. He pushed it a little harder than a Colt, but not as high pressured as you can load an original Vaquero.
Ruger did install some lighter springs, since that's something that many customers were doing anyway. Unless the internal surfaces are very rough, so that you need strong springs to overcome the drag, there's no reason to go with heavy springs. Strong enough to function, but not strong enough to cause premature wear, is a good level of spring force.